Rechargeable flashlights have been known and used for some time. Many flashlights are not constructed in a mechanically rugged fashion. The present invention relates to rechargeable flashlights which are distinguished by their rugged mechanical construction.
Many flashlights are constructed with a battery housing or casing that is made of an insulating material, for example, plastic. Special provision must then be made for a return current pathway for the lighting current. The present invention in its preferred form is directed to the type of flashlight construction that includes a metal housing for the battery. The metal housing itself is then used to provide the return current pathway for the illuminating current.
My U.S. Pat. No. 3,737,649 shows a flashlight of this type. As shown in that patent the metal housing for the batteries is of cylindrical configuration and threaded on its rearward end. A metal tail cap has a closed rearward end and is threaded at its open forward end. A compression spring carried by the tail cap engages the rearward end of the rearmost one of the batteries. When the tail cap is tightened on the threads of the metal housing, the compression spring ensures a good electrical contact between each two adjacent ones of the batteries. It also provides a current pathway from the rearmost battery to the closed end of the tail cap.
In my U.S. Pat. No. 3,829,676 I have shown how a spare bulb for the flashlight can be carried inside the flashlight itself, simply by storing it inside the compression spring in a space that would otherwise be vacant.
In my U.S. Pat. No. 3,890,555 I have also shown a type of recharging circuit that can be used for the recharging of a rechargeable flashlight. According to the teaching of that patent the flashlight that is to be recharged is temporarily stored in a special housing devised for that express purpose, and of which the recharging circuit is a part.
U.S. Pat. No. 4,115,842 issued to Keller also shows a rechargeable flashlight supported in a special holder. Again, a recharging circuit is supported inside the holder.
According to the present invention the recharging circuit is contained within the housing of the flashlight itself. It is therefore not necessary to utilize a special holder for either the flashlight or the recharger circuit.
The object of the invention, therefore, is to provide a flashlight with built-in recharger circuit, which is economical to manufacture, which protects the recharger circuit from mechanical damage, and which is also convenient and reliable in its operation.